Efficient sharing mechanisms for virtualized multi-tenant heterogeneous networks

The explosion in data traffic, the physical resource constraints, and the insufficient financial incentives for deploying 5G networks, stress the need for a paradigm shift in network upgrades. Typically, operators are also the service providers, which charge the end users with low and flat tariffs, independently of the service enjoyed. A fine-scale management of the network resources is needed, both for optimizing costs and resource utilization, as well as for enabling new synergies among network owners and third-parties. In particular, operators could open their networks to third parties by means of fine-scale sharing agreements over customized networks for enhanced service provision, in exchange for an adequate return of investment for upgrading their infrastructures. The main objective of this thesis is to study the potential of fine-scale resource management and sharing mechanisms for enhancing service provision and for contributing to a sustainable road to 5G. More precisely, the state-of-the-art architectures and technologies for network programmability and scalability are studied, together with a novel paradigm for supporting service diversity and fine-scale sharing. We review the limits of conventional networks, we extend existing standardization efforts and define an enhanced architecture for enabling 5G networks' features (e.g., network-wide centralization and programmability). The potential of the proposed architecture is assessed in terms of flexible sharing and enhanced service provision, while the advantages of alternative business models are studied in terms of additional profits to the operators. We first study the data rate improvement achievable by means of spectrum and infrastructure sharing among operators and evaluate the profit increase justified by a better service provided. We present a scheme based on coalitional game theory for assessing the capability of accommodating more service requests when a cooperative approach is adopted, and for studying the conditions for beneficial sharing among coalitions of operators. Results show that: i) collaboration can be beneficial also in case of unbalanced cost redistribution within coalitions; ii) coalitions of equal-sized operators provide better profit opportunities and require lower tariffs. The second kind of sharing interaction that we consider is the one between operators and third-party service providers, in the form of fine-scale provision of customized portions of the network resources. We define a policy-based admission control mechanism, whose performance is compared with reference strategies. The proposed mechanism is based on auction theory and computes the optimal admission policy at a reduced complexity for different traffic loads and allocation frequencies. Because next-generation services include delay-critical services, we compare the admission control performances of conventional approaches with the proposed one, which proves to offer near real-time service provision and reduced complexity. Besides, it guarantees high revenues and low expenditures in exchange for negligible losses in terms of fairness towards service providers. To conclude, we study the case where adaptable timescales are adopted for the policy-based admission control, in order to promptly guarantee service requirements over traffic fluctuations. In order to reduce complexity, we consider the offline pre­computation of admission strategies with respect to reference network conditions, then we study the extension to unexplored conditions by means of computationally efficient methodologies. Performance is compared for different admission strategies by means of a proof of concept on real network traces. Results show that the proposed strategy provides a tradeoff in complexity and performance with respect to reference strategies, while reducing resource utilization and requirements on network awareness.La explosion del trafico de datos, los recursos limitados y la falta de incentivos para el desarrollo de 5G evidencian la necesidad de un cambio de paradigma en la gestion de las redes actuales. Los operadores de red suelen ser tambien proveedores de servicios, cobrando tarifas bajas y planas, independientemente del servicio ofrecido. Se necesita una gestion de recursos precisa para optimizar su utilizacion, y para permitir nuevas sinergias entre operadores y proveedores de servicios. Concretamente, los operadores podrian abrir sus redes a terceros compartiendolas de forma flexible y personalizada para mejorar la calidad de servicio a cambio de aumentar sus ganancias como incentivo para mejorar sus infraestructuras. El objetivo principal de esta tesis es estudiar el potencial de los mecanismos de gestion y comparticion de recursos a pequei\a escala para trazar un camino sostenible hacia el 5G. En concreto, se estudian las arquitecturas y tecnolog fas mas avanzadas de "programabilidad" y escalabilidad de las redes, junto a un nuevo paradigma para la diversificacion de servicios y la comparticion de recursos. Revisamos los limites de las redes convencionales, ampliamos los esfuerzos de estandarizacion existentes y definimos una arquitectura para habilitar la centralizacion y la programabilidad en toda la red. La arquitectura propuesta se evalua en terminos de flexibilidad en la comparticion de recursos, y de mejora en la prestacion de servicios, mientras que las ventajas de un modelo de negocio alternativo se estudian en terminos de ganancia para los operadores. En primer lugar, estudiamos el aumento en la tasa de datos gracias a un uso compartido del espectro y de las infraestructuras, y evaluamos la mejora en las ganancias de los operadores. Presentamos un esquema de admision basado en la teoria de juegos para acomodar mas solicitudes de servicio cuando se adopta un enfoque cooperativo, y para estudiar las condiciones para que la reparticion de recursos sea conveniente entre coaliciones de operadores. Los resultados ensei\an que: i) la colaboracion puede ser favorable tambien en caso de una redistribucion desigual de los costes en cada coalicion; ii) las coaliciones de operadores de igual tamai\o ofrecen mejores ganancias y requieren tarifas mas bajas. El segundo tipo de comparticion que consideramos se da entre operadores de red y proveedores de servicios, en forma de provision de recursos personalizada ya pequei\a escala. Definimos un mecanismo de control de trafico basado en polfticas de admision, cuyo rendimiento se compara con estrategias de referencia. El mecanismo propuesto se basa en la teoria de subastas y calcula la politica de admision optima con una complejidad reducida para diferentes cargas de trafico y tasa de asignacion. Con particular atencion a servicios 5G de baja latencia, comparamos las prestaciones de estrategias convencionales para el control de admision con las del metodo propuesto, que proporciona: i) un suministro de servicios casi en tiempo real; ii) una complejidad reducida; iii) unos ingresos elevados; y iv) unos gastos reducidos, a cambio de unas perdidas insignificantes en terminos de imparcialidad hacia los proveedores de servicios. Para concluir, estudiamos el caso en el que se adoptan escalas de tiempo adaptables para el control de admision, con el fin de garantizar puntualmente los requisitos de servicio bajo diferentes condiciones de trafico. Para reducir la complejidad, consideramos el calculo previo de las estrategias de admision con respecto a condiciones de red de referenda, adaptables a condiciones inexploradas por medio de metodologias computacionalmente eficientes. Se compara el rendimiento de diferentes estrategias de admision sobre trazas de trafico real. Los resultados muestran que la estrategia propuesta equilibra complejidad y ganancias, mientras se reduce la utilizacion de recursos y la necesidad de conocer el estado exacto de la red.Postprint (published version

DR9.3 Final report of the JRRM and ASM activities

Deliverable del projecte europeu NEWCOM++This deliverable provides the final report with the summary of the activities carried out in NEWCOM++ WPR9, with a particular focus on those obtained during the last year. They address on the one hand RRM and JRRM strategies in heterogeneous scenarios and, on the other hand, spectrum management and opportunistic spectrum access to achieve an efficient spectrum usage. Main outcomes of the workpackage as well as integration indicators are also summarised.Postprint (published version

Contributing to the pathway towards 5G experimentation with an SDN-controlled network box

Καθώς η απαίτηση σε ευρυζωνικές υπηρεσίες κινητών επικοινωνιών αυξάνεται ραγδαία, τα υπάρχοντα δίκτυα κινητών επικοινωνιών πλησιάζουν τα όριά τους κάνοντας επιτακτική την ανάγκη εξέλιξής τους η οποία θα επέλθει με την τεχνολογική άφιξη της επόμενης γενιάς κινητών επικοινωνιών, ευρέως γνωστής ως 5G. Το 5G μεταφέρει όλες εκείνες τις δυνατότητες οι οποίες είναι απαραίτητες για να καλυφθούν οι συνεχώς αυξανόμενες ανάγκες σε ευρυζωνικές υπηρεσίες, να υποστηρίξουν το Internet of Things καθώς και να ενοποιήσουν ετερογενείς υπηρεσίες σε διαφορετικές βιομηχανίες. Η παρούσα διπλωματική εργασία στοχεύει να παρουσιάσει το “Network in a box”, ένα καινοτόμο εργαλείο που αναπτύξαμε στο εργαστήριο, το οποίο βασίζεται επάνω στους θεμέλιους λίθους του 5G, το SDN και το NFV. Με το SDN να είναι η νέα προσέγγιση στα δίκτυα κινητών επικοινωνιών, ο έλεγχος διαχωρίζεται από τα δεδομένα παρέχοντας τη δυνατότητα οποιεσδήποτε αποφάσεις ελέγχου, να λαμβάνονται κεντρικά, μετατρέποντας έτσι τις κλασικές δικτυακές συσκευές σε απλά προωθητικά στοιχεία του δικτύου. Η συγκεκριμένη διάταξη μιμείται ένα πραγματικό δίκτυο, το οποίο διαθέτει δυνατότητες αυτο-οργάνωσης και αυτο-βελτίωσης, προσομοιώνοντας τη λειτουργία του 5G δικτύου. Το συγκεκριμένο εργαλείο είναι επίσης ικανό να παράσχει KPI μετρικές του 5G δικτύου κάτω από πραγματικές συνθήκες ενόσω αληθινές δικτυακές συσκευές είναι συνδεδεμένες σε αυτό. Η δομή της παρούσας διπλωματικής εργασίας αναλύεται σε πέντε κεφάλαια. Το πρώτο κεφάλαιο παρουσιάζει τις προκλήσεις που σύντομα θα κληθούν να αντιμετωπίσουν τα δίκτυα κινητών επικοινωνιών και πώς αυτές μπορούν να καλυφθούν με την τεχνολογία του 5G. Το δεύτερο κεφάλαιο εισάγει την τάση στην αγορά των κινητών επικοινωνιών που διαφένεται πίσω από την επερχόμενη άφιξη του 5G, αποκαλύπτοντας το επιχειρηματικό πλαίσιο για επιχειρήσεις, καταναλωτές και συνεργασίες όπως επίσης και κάποιες περιπτώσεις χρήσης που αντικατοπτρίζουν την διαρκή εξέλιξη στις ευρυζωνικές υπηρεσίες κινητών επικοινωνιών. Το τρίτο κεφάλαιο εμπεριέχει μια μικρή επισκόπηση των τρέχοντων έργων πάνω στο 5G, τα οποία ξεκίνησαν υπό την αιγίδα της Ευρωπαϊκής Επιτροπής με τη συνεργασία προμηθευτών τεχνολογίας επικοινωνιών, παρόχων υπηρεσιών, μικρομεσαίων επιχειρήσεων και πανεπιστημίων. Γίνεται επίσης αναφορά στις βασικές τεχνολογίες του 5G και στις δραστηριότητες προτυποποίησής του. Προχωρώντας στο τέταρτο κεφάλαιο, περιγράφουμε σε βάθος την αρχιτεκτονική του 5G δικτύου, αναλύοντας τα SDN, NFV, MANO και εξετάζουμε πώς αυτά συνεισφέρουν στη βιωσιμότητα του δικτύου. Τέλος, στο πέμπτο κεφάλαιο εισάγουμε μια καινοτόμο ιδέα που αναπτύξαμε στο εργαστήριο δικτύων του πανεπιστημίου μας, ένα πλήρως αυτόνομο δικτυακό εργαλείο, το “Network in a box”. Παρουσιάζουμε σε βάθος πώς αυτός ο server μπορεί να εγκατασταθεί και να λειτουργήσει καθώς και τις δυνατότητές του κάτω από πραγματικές συνθήκες λειτουργίας του δικτύου, ενώ λαμβάνουν χώρα υποβάθμιση ποιότητας ή μη-διαθεσιμότητα στις δικτυακές ζεύξεις, παρέχοντας επίσης μετρικές από τη λειτουργία του δικτύου σε πραγματικό χρόνο.As the demand in mobile broadband is tremendously increased and the heterogeneity of the services to be covered is growing rapidly, current mobile networks are close to their limits imposing the need of an evolution which is going to be introduced by the next generation technology, the ITU IMT-2020, well known as 5G. 5G brings all those capabilities required to cover the increased mobile broadband needs, support the Internet of Things and bind heterogeneous services in different industries. This diploma thesis aims at presenting the “Network in a box”, an innovative tool we developed which is based on the key 5G principles, SDN and NFV. With Software Defined Networking (SDN) being the new approach in mobile networks, control and data plane are decoupled providing the ability to make any control related decisions centrally and transform legacy network devices to simple forwarding elements. This testbed is a portable emulated network device which is self-managed and self-optimised and can be connected between any real network devices, emulating how the 5G network will perform. This plug & play black-box testbed is also capable of providing KPI metrics of the 5G network under real circumstances when real network devices are connected to it. The structure of this diploma thesis is decomposed in five chapters. Chapter 1 presents the challenges mobile networks will shortly face due to the growing heterogeneous demands in communications towards the year 2020 and beyond and how these can be met with the upcoming 5G technology. Chapter 2 introduces the market trend behind the new era of 5G, revealing the business context for enterprises, consumers, verticals and partnerships as well as some use cases which reflect the continuous mobile broadband evolution. Chapter 3 includes a short overview of the ongoing 5G projects, initiated under the umbrella of the European Commission, with the collaboration of communications technology vendors, telecommunications operators, service providers, small and medium-sized enterprises (SMEs) and universities. There is also a reference in 5G key enabling technologies and standardisation activities as we move towards the next generation mobile networks technology. Moving forward, chapter 4 describes in detail the technological components of 5G network architecture such as SDN, NFV, MANO and examines how these 5G key enabling technologies contribute to the overall networks’ sustainability. Finally, in chapter 5 we introduce an innovative idea developed in our university’s communications network research laboratory, an autonomous emulated portable network testbed, the “Network in a box”. We present in-depth how this portable server is deployed, operates and demonstrate the way it can be connected to real network elements emulating a real 5G end-to-end customer network. Moreover, in this last chapter we present “Network in a box” capabilities under real network circumstances when link degradations or failures take place, providing also real-time network metrics

A baseband wireless spectrum hypervisor for multiplexing concurrent OFDM signals

The next generation of wireless and mobile networks will have to handle a significant increase in traffic load compared to the current ones. This situation calls for novel ways to increase the spectral efficiency. Therefore, in this paper, we propose a wireless spectrum hypervisor architecture that abstracts a radio frequency (RF) front-end into a configurable number of virtual RF front ends. The proposed architecture has the ability to enable flexible spectrum access in existing wireless and mobile networks, which is a challenging task due to the limited spectrum programmability, i.e., the capability a system has to change the spectral properties of a given signal to fit an arbitrary frequency allocation. The proposed architecture is a non-intrusive and highly optimized wireless hypervisor that multiplexes the signals of several different and concurrent multi-carrier-based radio access technologies with numerologies that are multiple integers of one another, which are also referred in our work as radio access technologies with correlated numerology. For example, the proposed architecture can multiplex the signals of several Wi-Fi access points, several LTE base stations, several WiMAX base stations, etc. As it able to multiplex the signals of radio access technologies with correlated numerology, it can, for instance, multiplex the signals of LTE, 5G-NR and NB-IoT base stations. It abstracts a radio frequency front-end into a configurable number of virtual RF front ends, making it possible for such different technologies to share the same RF front-end and consequently reduce the costs and increasing the spectral efficiency by employing densification, once several networks share the same infrastructure or by dynamically accessing free chunks of spectrum. Therefore, the main goal of the proposed approach is to improve spectral efficiency by efficiently using vacant gaps in congested spectrum bandwidths or adopting network densification through infrastructure sharing. We demonstrate mathematically how our proposed approach works and present several simulation results proving its functionality and efficiency. Additionally, we designed and implemented an open-source and free proof of concept prototype of the proposed architecture, which can be used by researchers and developers to run experiments or extend the concept to other applications. We present several experimental results used to validate the proposed prototype. We demonstrate that the prototype can easily handle up to 12 concurrent physical layers

The Cloud-to-Thing Continuum

The Internet of Things offers massive societal and economic opportunities while at the same time significant challenges, not least the delivery and management of the technical infrastructure underpinning it, the deluge of data generated from it, ensuring privacy and security, and capturing value from it. This Open Access Pivot explores these challenges, presenting the state of the art and future directions for research but also frameworks for making sense of this complex area. This book provides a variety of perspectives on how technology innovations such as fog, edge and dew computing, 5G networks, and distributed intelligence are making us rethink conventional cloud computing to support the Internet of Things. Much of this book focuses on technical aspects of the Internet of Things, however, clear methodologies for mapping the business value of the Internet of Things are still missing. We provide a value mapping framework for the Internet of Things to address this gap. While there is much hype about the Internet of Things, we have yet to reach the tipping point. As such, this book provides a timely entrée for higher education educators, researchers and students, industry and policy makers on the technologies that promise to reshape how society interacts and operates